1. Field of the Invention
The present invention relates to a liquid crystal display, and more particularly to a liquid crystal display that is capable of preventing optical sheets from being damaged and wrinkled by a panel guide.
2. Discussion of the Related Art
Generally, as shown in FIG. 1 and FIG. 2, a liquid crystal module used as a display device in a notebook computer includes a main frame 14 received with a backlight assembly, a panel guide 12 attached to the upper portion of the main frame 14 in parallel, a liquid crystal panel 2 loaded onto the panel guide 12, a top case 16 for surrounding the edge of the liquid crystal panel 2 and the side of the main frame 14, and a bottom case 10 contacting the side of the top case 16 to surround the bottom of the liquid crystal module. As shown in FIG. 2, the backlight assembly includes a lamp housing 18 mounted with a lamp 20, a light guide 6 for converting a light inputted from the lamp 20 into a surface light source, and optical sheets 4 attached to the light guide to improve the efficiency of light incident to the liquid crystal panel 2. The optical sheets 4 consist of a plurality of stacked sheets such as a diffusion sheet, a prism sheet, a protective sheet and the like. The main frame 14 is usually made from a mold material, a metal or the like to fix and support the backlight assembly. The panel guide 12 is molded from a resin material such as polycarbonate, etc. and is attached to the upper portion of the main frame 14 to support the liquid crystal panel 2 from the lower portion thereof. In this panel guide 12, a jaw or stepped prominence is provided at the upper surface of a panel loader loaded with a liquid crystal panel 2 so that the liquid crystal panel can be secured thereto. The sides of top case 16 and the bottom case 10 overlap one another and are fixed together by a screw. In the liquid crystal panel 2, a liquid crystal is injected between two sheets of glass substrates. A polarizer is attached to each sheet of glass substrate. The liquid crystal pixel cells are arranged in a matrix. Each liquid crystal pixel cell is driven with a thin film transistor (TFT). A tape carrier package (TCP) 22 mounted with drive integrated circuits (IC's) is provided between a signal line pad formed at the edge of the liquid crystal panel 2 and a printed circuit board (PCB) 8 installed under the main frame 14. A gasket 24 for shielding against electromagnetic interference (EMI) is provided between the PCB 8 and the bottom case 10.
However, a gap of about 0.4±α(for example 0.4±0.1 mm) exists between the panel guide 12 and the optical sheet 4. A thickness of the panel loader in the panel guide 12 is set to approximately 0.7 to 0.8 mm as shown in FIG. 3. This causes the problem that the panel guide 12 is pressed down by a load of the liquid crystal panel 2 itself or a pressure generated upon assembly, etc. to pressurize the optical sheet 4 in the conventional liquid crystal module. If the edge of the optical sheet 4 is pressed down by the panel guide 12, then the corresponding portion of the optical sheet 4 is wrinkled or damaged and results in a dark display portion on the picture display at the edge of the optical sheet 4. In the conventional liquid crystal module, also, the liquid crystal is deteriorated and the optical sheets 4 wrinkle due to heat that is generated in the lamp 20 and applied to the liquid crystal panel 2 through the gap between the panel guide 12 and the backlight assembly. Furthermore, the conventional liquid crystal module has a problem in that a short between the pads or the patterns is generated by a foreign substance flowing into the liquid crystal panel 2, the PCB 8 and the TCP 22 via the gap upon change of the backlight assembly or in an assembly process of the liquid crystal module.